This document is a Mac OS X manual page. Manual pages are a command-line technology for providing documentation. You can view these manual pages locally using the man(1) command. These manual pages come from many different sources, and thus, have a variety of writing styles.

This manual page is associated with the Mac OS X developer tools. The software or headers described may not be present on your Mac OS X installation until you install the developer tools package. This package is available on your Mac OS X installation DVD, and the latest versions can be downloaded from developer.apple.com.

For more information about the manual page format, see the manual page for manpages(5).

SOCKETPAIR(2)               BSD System Calls Manual              SOCKETPAIR(2)

NAME
     socketpair -- create a pair of connected sockets

SYNOPSIS
     #include <sys/socket.h>

     int
     socketpair(int domain, int type, int protocol, int socket_vector[2]);

DESCRIPTION
     The socketpair() call creates an unnamed pair of connected sockets in the specified domain domain, of
     the specified type, and using the optionally specified protocol.  The descriptors used in referencing
     the new sockets are returned in socket_vector[0] and socket_vector[1].  The two sockets are indistin-guishable. indistinguishable.
     guishable.

RETURN VALUES
     The socketpair() function returns the value 0 if successful; otherwise the value -1 is returned and the
     global variable errno is set to indicate the error.

ERRORS
     The call succeeds unless:

     [EAFNOSUPPORT]     The specified address family is not supported on this machine.

     [EFAULT]           The address socket_vector does not specify a valid part of the process address
                        space.

     [EMFILE]           No more file descriptors are available for this process.

     [ENFILE]           No more file descriptors are available for the system.

     [ENOBUFS]          Insufficient resources were available in the system to perform the operation.

     [ENOMEM]           Insufficient memory was available to fulfill the request.

     [EOPNOTSUPP]       The specified protocol does not support creation of socket pairs.

     [EPROTONOSUPPORT]  The specified protocol is not supported on this machine.

     [EPROTOTYPE]       The socket type is not supported by the protocol.

LEGACY SYNOPSIS
     #include <sys/types.h>
     #include <sys/socket.h>

     The include file <sys/types.h> is necessary.

SEE ALSO
     pipe(2), read(2), write(2), compat(5)

BUGS
     This call is currently implemented only for the UNIX domain.

HISTORY
     The socketpair() function call appeared in 4.2BSD.

4.2 Berkeley Distribution        June 4, 1993        4.2 Berkeley Distribution